1. Field of the Invention
The present invention relates to a current-inducing-type surface-mount-type antenna for use in mobile communication equipment, such as portable telephones, and a radio LAN (Local Area Network), and communication equipment using the same.
2. Description of the Related Art
A conventional surface-mount-type antenna is shown in FIG. 8. A radiation electrode 72 and a power supply electrode 73 are formed on the surface of a base 71 of this surface-mount-type antenna 70 with a gap g therebetween. A grounding terminal 72a and a power supply electrode 73a, which are connected to one end of the radiation electrode 72 and to one end of the power supply electrode 73, are formed on one end surface 71a of the base 71. A capacity loaded electrode 74 is formed on the other end surface 71b of the base 71, which capacity loaded electrode 74 is connected to the other end of the radiation electrode 72.
In the conventional surface-mount-type antenna 70, the capacity loaded electrode 74 is provided for shortening the wavelength. However, the capacitance formed by this capacity loaded electrode 74 can be increased only by the specific inductive capacity er of the base 71 and the thickness of the base 71. Also, even if the radiation electrode 72 is formed into a meandering shape in order to increase the length of the radiation electrode 72 which resonates at a predetermined wavelength, there are limitations in terms of dimensions and shape, and the length of the base 71 cannot be made short. Therefore, it is difficult to achieve a small size with the conventional surface-mount-type antenna 70. Further, communication equipment having the conventional surface-mount-type antenna 70 incorporated therein has the drawback of the housing of the communication equipment being incapable of being formed to be small in size.